S08.4 INFECTION OF THE TOTAL SHOULDER ARTHROPLASTY

Abstract

The infected total shoulder arthroplasty is not a frequent finding at the present time, the necessity of treating this complication may become more urgent with the continually increasing number of arthroplasty procedures performed.

From 1992 till the beginning of 2005, eleven patients were treated for infected total shoulder arthroplasty. An acute infection occurred in one patient (9 %), subacute in three (27 %) and late in seven patients (64 %). The average period between the primary operation and infection manifestation was 19.3 months.

The group of 181 patients operated on for shoulder replacement between 1992 and 2005 was evaluated, and a deep infection of total shoulder arthroplasty was found in 11 patients (2.2 %).

An antibiotic therapy alone was sufficient to eradicate the infeciton in only 20 % of the infected patients, but these showed good Constant scores (average, 42 points). Revision surgery, debridement and irrigation drainage had a low success rate (33 %) and good Constant scores (average, 45 points) in the cured patients. A two-stage exchange was 100 % successful but had a poor outcome, with an average Constant score of 26 points. However, a two-stage exchange involving a spacer had both 100 % success rate and a good outcome with an average Constant score of 49 points. On statistical evaluation using the unpaired t-test, there was a significant difference in the Constant scores (T 4.35 p=0.005) between the patients undergoing exchange arthroplasty with (n=40) and without (n=4) the spacer.

Poor function scores after resection arthroplasty are not surprising, because a sharp residual proximal humerus is likely to irritate soft tissues and, in addition, it is not possible to reconstruct a rotator cuff to match it.

Comparing the results of one-stage with two-stage reimplantation is a complex issue. Attention should be paid to a relationship between the methods routinely used to treat an infected total shoulder arthroplasty and those preferred by the given hospital for treatment of other joints. If the therapy is well established in that hospital and gives good long-term results, it is optimal to use it also for the treatment of infected total shoulder arthroplasty.

The method of treating infected total shoulder arthroplasty is not different from other big joint therapies. The use of a spacer will allow us to remodel soft tissues satisfactorily even after extensive debridement. The functional results of treatment involving a spacer are significantly better.